Closures such as windows pivotally connected within their frames are widely known. A rectangular frame in which a pane of glass is mounted is generally pivotally connected to a surrounding frame by one or more hinges having either a horizontal or vertical pivotal axis. Especially common is a window having an inner frame pivotally mounted to an outer frame along an upper cross-member in which window may be opened by pushing a lower cross-member of the inner frame outwardly into an open position.
A variety of devices is known for securing such a window in its closed position.
One device includes a handle rotatably mounted to a lower portion of the inner frame of the window and a striker plate mounted to the lower cross-member of the outer frame into which a portion of the handle may be rotated to engage the plate. The engaging portion of the handle is generally tapered to engage the striker plate as the handle is rotated into its fully closed position so that the movable inner frame is drawn into a tightly closed position with respect to the outer surrounding frame.
Another type of device, which avoids the need for a striker plate, is described in U.S. Patent No. 4,826,222 which issued May 2, 1989 to Davis. The patent specification describes a closure latch having a handle which rotates in a plane and having movement which is coupled to a pivotal plate which can be moved into position to overlie and engage a window frame.